As an example of this kind of control valve, there is known an electromagnetic valve in which a differential pressure valve for releasing a passage when a front/rear differential pressure is equal to or higher than a predetermined pressure is provided in an inflow passage or an outflow passage with respect to a main valve body (for example, see Patent Document 1 below).
In the above-described conventional electromagnetic valve, a fluid flow direction inside the valve is defined to one direction (a direction from the inflow passage to the outflow passage) by the differential pressure valve provided in the inflow passage or the outflow passage.